The article reviews the forms and natural levels of carbon, nitrogen, and phosphorus in world rivers, focusing on dissolved and particulate forms, organic and inorganic species. The study highlights that dissolved organic carbon (DOC) levels vary from 1 to 20 mg/l, with an average of 5.75 mg/l, while particulate organic carbon (POC) is inversely related to suspended matter, ranging from 0.5 to 40% of total suspended matter. The DOC/TOC ratio is highly variable, typically around 0.6, but can be much lower in highly erosive environments. Nitrogen forms include dissolved organic nitrogen (DON), dissolved inorganic nitrogen (DIN), and particulate organic nitrogen (PON), with DIN levels ranging from 120 μg/l to 240 μg/l. DON levels are less studied but estimated to be around 260 μg/l. Phosphorus levels are very low, with orthophosphate (P-PO4) ranging from 1 to 24 μg/l, and total dissolved phosphorus (TDP) including organic forms. The average nutrient content of rains is estimated, and the article discusses the impact of human activities on nutrient levels, noting that total dissolved phosphorus and nitrogen have increased globally due to human influence. The article also presents methods for estimating nutrient transport by rivers and compares different budgeting approaches.The article reviews the forms and natural levels of carbon, nitrogen, and phosphorus in world rivers, focusing on dissolved and particulate forms, organic and inorganic species. The study highlights that dissolved organic carbon (DOC) levels vary from 1 to 20 mg/l, with an average of 5.75 mg/l, while particulate organic carbon (POC) is inversely related to suspended matter, ranging from 0.5 to 40% of total suspended matter. The DOC/TOC ratio is highly variable, typically around 0.6, but can be much lower in highly erosive environments. Nitrogen forms include dissolved organic nitrogen (DON), dissolved inorganic nitrogen (DIN), and particulate organic nitrogen (PON), with DIN levels ranging from 120 μg/l to 240 μg/l. DON levels are less studied but estimated to be around 260 μg/l. Phosphorus levels are very low, with orthophosphate (P-PO4) ranging from 1 to 24 μg/l, and total dissolved phosphorus (TDP) including organic forms. The average nutrient content of rains is estimated, and the article discusses the impact of human activities on nutrient levels, noting that total dissolved phosphorus and nitrogen have increased globally due to human influence. The article also presents methods for estimating nutrient transport by rivers and compares different budgeting approaches.